Flathead National Forest Area, Montana
The dominant drainage class is and the dominant hydrologic group is C (slow infiltration, moderate runoff). This report summarizes the major soil map units across the survey area to help you understand what to expect when buying, building, or gardening in Flathead National Forest Area, Montana.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Andic Cryochrepts-Andeptic Cryoboralfs association, glacial trough walls | 201K | D | Very limited | Very limited | |
| Cirqueland-Entic Cryandepts complex, very steep | 153K | Not rated | Not rated | ||
| Andeptic Cryoboralfs, silty till substratum, hilly | 93K | C | Very limited | Very limited | |
| Andeptic Cryoboralfs-Andic Cryochrepts complex, steep | 85K | C | Very limited | Very limited | |
| Andeptic Cryoboralfs, silty till substratum, rolling | 78K | C | Very limited | Very limited | |
| Rock outcrop-Ochrepts complex, structural breaklands | 77K | D | Not rated | Not rated | |
| Andeptic Cryoboralfs-Andic Cryochrepts complex, hilly | 69K | C | Very limited | Very limited | |
| Andic Cryochrepts, glaciated mountain ridges | 64K | D | Very limited | Very limited | |
| Andic Cryochrepts, glaciated mountain slopes | 63K | D | Very limited | Very limited | |
| Andic Cryochrepts-Entic Cryandepts-Rock outcrop complex, cirque basins | 63K | C | Very limited | Very limited | |
| Andeptic Cryoboralfs, silty till substratum, calcareous, hilly | 51K | C | Very limited | Very limited | |
| Dystric Eutrochrepts, till substratum | 50K | A | Very limited | Very limited | |
| Water | 37K | Not rated | Not rated | ||
| Typic Eutroboralfs, silty till substratum, rolling | 32K | B | Very limited | Very limited | |
| Dystric Cryochrepts, till substratum-Dystric Cryochrepts, residuum substratum complex, steep | 28K | C | Very limited | Very limited | |
| Ochrepts-Rock outcrop complex, southerly aspects | 27K | A | Very limited | Very limited | |
| Andeptic Cryoboralfs, silty till substratum, steep | 26K | C | Very limited | Very limited | |
| Andic Cryochrepts-Entic Cryandepts-Rock outcrop complex, cirque basins, steep | 25K | C | Very limited | Very limited | |
| Andeptic Cryoboralfs, silty till substratum, calcareous, rolling | 23K | C | Very limited | Very limited | |
| Andeptic Cryoboralfs, silty till substratum, calcareous, steep | 23K | C | Very limited | Very limited |
What This Means
Building & Foundations
About 79% of soils are rated "very limited" for dwellings with basements. Specific challenges include steep slopes. A geotechnical assessment is recommended before building.
Septic Systems
About 79% of soils are rated "very limited" for septic absorption fields. Engineered or alternative systems are frequently required. Always get a professional perc test before purchasing land that needs septic.
Gardening & Agriculture
Drainage is generally favorable for gardening. Adding compost and mulch will improve fertility and water retention. Test your soil's pH before planting — most vegetables prefer 6.0-7.0.